Varför är organiskt material både reaktivt och uthålligt? (REACT)

Organic matter (OM) degradation is key to mobilizing the greenhouse gas CO2 from soils and freshwater ecosystems which can influence climate change. The reactivity of OM is highly variable. In fact, OM can be lost within minutes or persist for millennia.

Currently, OM degradation rates contain a geat deal of uncertainty and we have highly different conceptualizations of what controls on OM degradation across soil and freshwater ecosystems.

The overall aim of REACT is to resolve diverging theories and build a unifying conceptualization of controls on OM reactivity and persistence that is valid across ecosystems.

REACT has three main aims:1) Consistent quantification of OM degradation rates across a wide set of terrestrial and freshwater ecosystems in relation to ecosystem properties and the detailed molecular composition of OM.2) Identify key limiting biological and physico-chemical rate limiting steps for OM degradation pathways.

Controlled lab experiments will test the importance of two ecosystem properties (enzymes and inorganic particles) relative to detailed molecular composition.3) Synthesis towards a more unified conceptual framework for OM degradation.Results from aims 1) and 2) will test the limits of exisitng theories and aid in the development of a more robust understanding of why OM reactivity is highly variable.

The PI has a rare multidisiplinary expertise across soil science, limnology and analytical chemistry to critcially attack the aims within REACT.